Correlation between MR imaging - prognosis factors and molecular classification of breast cancers.

The molecular classification of breast cancers defines subgroups of cancer with different prognoses and treatments. Each molecular type representing the intrinsic signature of the cancer corresponds to a histological profile incorporating hormone receptors, HER2 status and the proliferation index. This article describes the correlations between this molecular classification obtained in routine clinical practice using histological parameters and MRI. It shows that there is a specific MRI profile for triple-negative cancers: distinct demarcation, regular edges, hyperintensity on T2 weighted signals and, particularly, a crown enhancement. It is important for the radiologist to understand this molecular classification, firstly because of the relatively suggestive appearance of triple-negative basal-like cancers in the molecular classification, secondly, and particularly, as cancers in patients with the BRCA1 mutation are often triple-negative meaning that the criteria for reading the MRI needs to be tailored to this feature of the cancers, and finally because the efficacy of MRI in assessing response to neoadjuvant chemotherapy depends on the molecular class of cancer treated.

Mechanical occlusions: diagnostic traps and key points of the report.

Management of mechanical occlusion, particularly of the small intestine, has altered considerably over recent years, with a change of paradigm and the indication for surgery depending on the cause of the occlusion and any signs of entrapment or strangulation. It is therefore important today to make a positive diagnosis of mechanical occlusion, to assess its degree, its location and its cause, and to look for signs of entrapment and strangulation. Only computer tomography can provide the answers to these different questions. The aim of this paper is to provide a reminder of the CT signs that enable us to confirm diagnosis of the various aspects of mechanical occlusion of the stomach and duodenum, small intestine or colon, to emphasize and illustrate the diagnostic traps in CT and to set out the key points of a CT report of mechanical occlusion.

Infection of the right iliac fossa.

Febrile pain in the right iliac fossa is one of the most common reasons for consulting at an emergency service. Within this framework, the main diagnosis that is considered is appendicitis, the main complication of which is perforation. However, a certain number of other conditions can be responsible for this clinical picture, primarily including digestive tract and mesentery disorders including mesenteric lymphadenitis, Crohn's disease, infectious enterocolitis, small intestine or colonic diverticulitis, ischaemic colitis or cancer of the caecum. This article illustrates the imaging semiology of the various right colonic, iliac, mesenteric and appendicular conditions that could potentially cause an infection of the right iliac fossa. It specifies the indications of ultrasound and CT scans, respectively, which depend on the age of the patient and the clinical signs and symptoms. Though the CT scan is commonly used in abdominal emergencies in general, and particularly in clinical pictures of infection of the right iliac fossa, ultrasound remains recommended as first line imaging when confronted with suspected appendicitis or lymphadenitis in a young subject or in the monitoring of Crohn's disease.